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1// SPDX-License-Identifier: GPL-2.02/*3 * Memory Bandwidth Monitoring (MBM) test4 *5 * Copyright (C) 2018 Intel Corporation6 *7 * Authors:8 * Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,9 * Fenghua Yu <fenghua.yu@intel.com>10 */11#include "resctrl.h"12 13#define RESULT_FILE_NAME "result_mbm"14#define MAX_DIFF_PERCENT 815#define NUM_OF_RUNS 516 17static int18show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, size_t span)19{20 unsigned long sum_bw_imc = 0, sum_bw_resc = 0;21 long avg_bw_imc = 0, avg_bw_resc = 0;22 int runs, ret, avg_diff_per;23 float avg_diff = 0;24 25 /*26 * Discard the first value which is inaccurate due to monitoring setup27 * transition phase.28 */29 for (runs = 1; runs < NUM_OF_RUNS ; runs++) {30 sum_bw_imc += bw_imc[runs];31 sum_bw_resc += bw_resc[runs];32 }33 34 avg_bw_imc = sum_bw_imc / 4;35 avg_bw_resc = sum_bw_resc / 4;36 avg_diff = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc;37 avg_diff_per = (int)(avg_diff * 100);38 39 ret = avg_diff_per > MAX_DIFF_PERCENT;40 ksft_print_msg("%s Check MBM diff within %d%%\n",41 ret ? "Fail:" : "Pass:", MAX_DIFF_PERCENT);42 ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per);43 ksft_print_msg("Span (MB): %zu\n", span / MB);44 ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);45 ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);46 47 return ret;48}49 50static int check_results(size_t span)51{52 unsigned long bw_imc[NUM_OF_RUNS], bw_resc[NUM_OF_RUNS];53 char temp[1024], *token_array[8];54 char output[] = RESULT_FILE_NAME;55 int runs, ret;56 FILE *fp;57 58 ksft_print_msg("Checking for pass/fail\n");59 60 fp = fopen(output, "r");61 if (!fp) {62 ksft_perror(output);63 64 return -1;65 }66 67 runs = 0;68 while (fgets(temp, sizeof(temp), fp)) {69 char *token = strtok(temp, ":\t");70 int i = 0;71 72 while (token) {73 token_array[i++] = token;74 token = strtok(NULL, ":\t");75 }76 77 bw_resc[runs] = strtoul(token_array[5], NULL, 0);78 bw_imc[runs] = strtoul(token_array[3], NULL, 0);79 runs++;80 }81 82 ret = show_bw_info(bw_imc, bw_resc, span);83 84 fclose(fp);85 86 return ret;87}88 89static int mbm_init(const struct resctrl_val_param *param, int domain_id)90{91 int ret;92 93 ret = initialize_mem_bw_imc();94 if (ret)95 return ret;96 97 initialize_mem_bw_resctrl(param, domain_id);98 99 return 0;100}101 102static int mbm_setup(const struct resctrl_test *test,103 const struct user_params *uparams,104 struct resctrl_val_param *p)105{106 int ret = 0;107 108 /* Run NUM_OF_RUNS times */109 if (p->num_of_runs >= NUM_OF_RUNS)110 return END_OF_TESTS;111 112 /* Set up shemata with 100% allocation on the first run. */113 if (p->num_of_runs == 0 && resctrl_resource_exists("MB"))114 ret = write_schemata(p->ctrlgrp, "100", uparams->cpu, test->resource);115 116 p->num_of_runs++;117 118 return ret;119}120 121static int mbm_measure(const struct user_params *uparams,122 struct resctrl_val_param *param, pid_t bm_pid)123{124 return measure_mem_bw(uparams, param, bm_pid, "reads");125}126 127static void mbm_test_cleanup(void)128{129 remove(RESULT_FILE_NAME);130}131 132static int mbm_run_test(const struct resctrl_test *test, const struct user_params *uparams)133{134 struct resctrl_val_param param = {135 .ctrlgrp = "c1",136 .filename = RESULT_FILE_NAME,137 .init = mbm_init,138 .setup = mbm_setup,139 .measure = mbm_measure,140 };141 int ret;142 143 remove(RESULT_FILE_NAME);144 145 ret = resctrl_val(test, uparams, uparams->benchmark_cmd, ¶m);146 if (ret)147 return ret;148 149 ret = check_results(DEFAULT_SPAN);150 if (ret && (get_vendor() == ARCH_INTEL))151 ksft_print_msg("Intel MBM may be inaccurate when Sub-NUMA Clustering is enabled. Check BIOS configuration.\n");152 153 return ret;154}155 156static bool mbm_feature_check(const struct resctrl_test *test)157{158 return resctrl_mon_feature_exists("L3_MON", "mbm_total_bytes") &&159 resctrl_mon_feature_exists("L3_MON", "mbm_local_bytes");160}161 162struct resctrl_test mbm_test = {163 .name = "MBM",164 .resource = "MB",165 .vendor_specific = ARCH_INTEL,166 .feature_check = mbm_feature_check,167 .run_test = mbm_run_test,168 .cleanup = mbm_test_cleanup,169};170